Dosatron Water Powered Nutrient Doser

[BillFarthing]

Dosatron are inline fertilizer injectors. They dose consistently regardless of the pressure. I am thinking about setting some of these up to automate the room like a PPK system.

Does anyone have any experience using these? Are there any negatives or things I should watch out for?

 

[queequeg152]

i dont think you can go wrong with a dosatron period... they just cost a grip.

they use them in everything... parts kits are available... they have service reps to talk to etc.

they really are top notch, just make sure you are getting the correct sized unit for you. there are some super cheap ones that are fixed rate( though that might be a different company?) that might be suitable to some, but i think in general you want the ones that can adjust on the fly.

again though you should be able to speak to a rep, and they can set you straight pretty quickly.

 

[Limeygreen]

They work well, but remember that it is designed for roughly 14 gpm and there are higher models as well, they used to sell a 11 gpm but stopped due to not much demand. They go from 0.1 % I think to 2 % of your fertilizer, usually I am running them around 1 to 1.5% depending. If you are running more than one fertilizer such as an a b system you need to put a mixing tube before it goes in line (2 inch pipe works well that is around 3 feet long) so that the fertilizers are mixing with water prior to going inline and prevent from making gypsum in your drip lines or other irrigation systems and hoses etc. It is very simple to do and if you need a hand shoot me a pm. But more or less you run the dosatrons inline with each other then the outlet of the last one you put into the mixing tube at the top and the outlet at the bottom to your inlet of your irrigation system. Don't forget a screen filter (200 mesh should do) regardless of single or multiple dosatrons to save drip lines or other irrigation equipment and make sure to check it often, once a day at first then see how long it takes to need a cleaning. Depending who you buy them from at a retail shop you could be looking around 600-700 cdn per unit starting at the 14 gpm.
Check your ec and pH often when using them especially with multi dosatrons as you will see a drift such as low pH to start then the pH raises as the days go on.
They are pretty good little machines for low tech uses, you can get gear dosers (not sure if that's what you call them) that have a wheel that spins and rubs the suction hose to make it a siphon and hooked to an ec metre and pH metre, handy units but more expensive. All depends on what you need, if you have any more questions let me know and I will see if I can help as I only know them briefly so far.

The other brand would be mix rite I believe, no idea about them but some people rave about them.

 

[queequeg152]

11 gpm?

did they stop selling that coke can sized one that goes down to very low rates?

 

[queequeg152]

11 gpm cannot be rite... they use these things in all the car washes to pump the various soaps... those carwashes are very low flow typically.

 

[Lazyman]

I cant imagine trying to dial that in, my nute schedule is essentially H&G , but for 12 weeks its a different formula every week, and uses like 11 different chems. You MIGHT be able to dial in a simpler recipe, but the week to week changes would make it a pain.

 

[Limeygreen]

http://www.dosatronusa.com/d07re125/

0.02 - 3 gpm

You just have to check with a drip bucket or you stock tank that the fertilizer is coming out of your dosatron is what you want.

Mixing fertilizers is fine, don't mix calcium with sulfates or phosphates unless you like calcium sulfate and calcium phosphate sludge that solidifies.

Calcium nitrate and magnesium sulfate different tanks, phosphate is same tank as sulfate. A B system is a tank that keeps these separate then mix in the injector to your irrigation tank/mixing tube.

One example:
A tank
Calcium nitrate
Potassium nitrate
Iron Chelate
Calcium Chloride

B Tank
Potassium nitrate
Potassium sulfate
Potassium chloride
Magnesium nitrate
Magnesium sulfate
Mono Potassium Phosphate
Phosphoric Acid
Borax
Zinc Sulfate
Copper Sulfate
Sodium Molybdate
Manganese Sulfate

These are examples of what usually may go into an A B system for the fertilizer concentrate solutions. Not all the fertilizers are put in, it depends on crop, grower and recipe.

Single stock Solution is simple as well you just dump into one tank and dial in what you need.

Some fertilizers come with instructions even if 2 part system then tell you how concentrated to make it and which dilution ratio to use usually for ppm of N.

It is not really that much work it's just checking to make sure everything is doing what it is supposed to.

 

[queequeg152]

i would think 2 dosatrons are a minimum.

maby three if you want to get crazy... but should just add the acid into the cal nitrate tank.

 

[Limeygreen]

Phosphoric acid in the Epsom tank is recommended it helps dissolve more of the fertilizer, nitric acid in the calcium tank. If you're using any chelated minors, acid will destroy the chelating agent but won't affect the minors that are sulfates.

 

[queequeg152]

epsom salt is insanely soluble... it does not need acid to further dissolve.

i would put the acid in the nitrate tank personally.

 

[BillFarthing]

i would think 2 dosatrons are a minimum.

maby three if you want to get crazy... but should just add the acid into the cal nitrate tank.

I looked into ferts suitable for one dosatron. Jack's HydroFeed is close, but it has urea as a source of nitrogen, which I would stay away from for cannabis.

I think a better solution would be Jack's hydro 2-part with a couple Dosatrons. I'm sure SuperWeed's system in the thread that I linked to looks fire.

Phosphoric acid in the Epsom tank is recommended it helps dissolve more of the fertilizer, nitric acid in the calcium tank. If you're using any chelated minors, acid will destroy the chelating agent but won't affect the minors that are sulfates.

I've been doing this for a long time and that's a great tip. Thank you!

 

[queequeg152]

Bump

Want to try jacks/calnit/epsom salts/ph down.

Can I mix the calnit,epsom,& down in the same bucket?

absolutly not.

sulfate will precipitate. you can mix calcium nitrate with pretty much any acid however.

 

[bsgospel]

I believe the same is true with silica. And precipitates insanely quick.


Edit: It's not as simple as 'ites' here 'ates' there. Here's an example of a dry fert/salt tank breakdown that has not caused any precipitation for me in the past and actually performed admirably.
Tank A- Ultrasol K+, Calcinit, micro nutes (Potassium/calcium/magnesium nitrate)
Tank B - Magriculture, PeaK, P-acid (Ammonium/Potassium/Magnesium sulfate, mono potassium phosphate)
Tank C - AgSil (potassium silicate)
Then through a mixer and ph/ec monitor controller.

 

[queequeg152]

silicates are just shitty at staying in solution in general.

if you have much tds at all it will precipitate.

i tried to follow that papers reccomendation of 100mg/l at like weekly intervals... it was a disaster.

silica seems to coagulate though... so it does not form a very bad turbidity. none of my drippers got clogged.

silicate at 10mg/l 24/7 is possible with most nutrient profiles... but i after doing it for a few weeks i got bored of silicate.

 

[Limeygreen]

Do not mix any sulfates with calcium nitrate, you will get free gypsum that precipitates to the bottom of your tank and if left too long you will need to chisel it out.

Silica can be put in a tank by itself and dripped in continuously or applied on a weekly basis as a one shot additive and there are many products available for this, the ones made available for plant uptake can be quite expensive though, silamol is a great product and can be sprayed as a foliar or dripped but must be used when mixed. I have used silica phosphate as a foliar on hydroponic vegetables once a week and it has good results that way as well.

 

[bsgospel]

Do not mix any sulfates with calcium nitrate, you will get free gypsum that precipitates to the bottom of your tank and if left too long you will need to chisel it out.

Silica can be put in a tank by itself and dripped in continuously or applied on a weekly basis as a one shot additive and there are many products available for this, the ones made available for plant uptake can be quite expensive though, silamol is a great product and can be sprayed as a foliar or dripped but must be used when mixed. I have used silica phosphate as a foliar on hydroponic vegetables once a week and it has good results that way as well.

You're right, I hadn't looked at my doser spreadsheet in a minute (and I'm no chemist.) I'm amending that post now.

 

[f-e]

And so, a few years went by, until 2019, when..


I have a one part feed, which works with RO. It's all in there. They once did a hard water version, which they said had more nitric acid in it. Twice now I have mixed enough Nitric into the feed bottle, to make it right for my tap. I have tap water about ph8 and an ec around 0.3 To which I pour my ready mixed potion until the truncheon says 1.4 and I know the pH is good. I have had a mix undisturbed for 6 weeks, then put it to use with no obvious problems.

I think I'm ready to have a crack at this, using just one doser on the tank fill.

I tried pouring in another brands PK, and made milk.


I'm a bit concerned that I won't get to shake the bottle every day. Manageable as that is, the riser from the bottle to the injector is niggling at me. Looking at aeroponics, things fall out of solution like bricks from the sky. 24 hours the column of feed will be stood in that pipe. There has to be some guidelines.


I see Aliexpress is knocking out 0.4 - 4% units for $100 landed. That's what really brings me here. Does anyone know about these cheap one's. Not the doseatron. Which sounds like the name of a transformer that scratches a lot

 

[f-e]

When one bump isn't enough...

Correcting pH isn't always a requirement when using RO water or very low ppm water.

I once used my one part (growth technologies) coco feed with RO for an entire crop. I was messing it up at first by correcting the pH. The facts are, RO is fine, and the elements in my feed are fine. Both together have the buffering power of cotton wool against a freight train. pH was set by the medium. The feed went in at something awful like 4.0 but the rootzone and runoff were in the high 5's. The coco had a greater effect on pH than the minuscule amount of acid I needed to get that 4.0 up to ~5.4 (which was truly minuscule, as buffering action was next to nothing)

My problems came about through constant pH corrections. pH swings caused by levels of oxygen and co2 changing, had me running in circles making them ill for a week or two. Only logic stopped me adjusting the pH and feeding at 4.0 to get healthy plants.

I imagine many people are adjusting tanks made up with RO, quite pointlessly. There is actually a coco sticky saying don't bother to do the pH with low EC readings from the tap. I'm a bit shy of that idea, but I hope to be getting the idea across.


So clean water, one part feed, single fertiliser injector. Only for a week of so in bloom might you need a second injector. But if your RO is in a tank, you could just spend a week adding PK yourself.


$100 injectors on Ali. Anybody used them?
The seals in a dosatron. Are they standard O-rings?

 

[CrushnYuba]

When one bump isn't enough...

Correcting pH isn't always a requirement when using RO water or very low ppm water.

I once used my one part (growth technologies) coco feed with RO for an entire crop. I was messing it up at first by correcting the pH. The facts are, RO is fine, and the elements in my feed are fine. Both together have the buffering power of cotton wool against a freight train. pH was set by the medium. The feed went in at something awful like 4.0 but the rootzone and runoff were in the high 5's. The coco had a greater effect on pH than the minuscule amount of acid I needed to get that 4.0 up to ~5.4 (which was truly minuscule, as buffering action was next to nothing)

My problems came about through constant pH corrections. pH swings caused by levels of oxygen and co2 changing, had me running in circles making them ill for a week or two. Only logic stopped me adjusting the pH and feeding at 4.0 to get healthy plants.

I imagine many people are adjusting tanks made up with RO, quite pointlessly. There is actually a coco sticky saying don't bother to do the pH with low EC readings from the tap. I'm a bit shy of that idea, but I hope to be getting the idea across.


So clean water, one part feed, single fertiliser injector. Only for a week of so in bloom might you need a second injector. But if your RO is in a tank, you could just spend a week adding PK yourself.


$100 injectors on Ali. Anybody used them?
The seals in a dosatron. Are they standard O-rings?

I had 4 of The cheapo blue mixrite china clones. They came with extra seals. The issue is finding replacement metal springs! They do work well when They work well. Most New good units don't have metal anymore. They got tension bands of fancy plastic tension thingies. Im sure you could find a spring that would fit it SOMEWHERE.
I really really abused mine and They started to break after a year or so. trying to run way more flow then it could handle and i NEVER cleaned them.
Also, the pipe thread on it it's some obscure British standard thread. Its 3/4" but its not npt or mht thread! Which just means to plumb it in, you will need to buy the fittings online for 2$ instead of hardware store. They will be perfectly accurate until They break and if you don't abuse it, it won't break for yeaaars.

The thing is awesome brand name dosers aren't that much money. Every company makes a doser for under 200$ that can do up to 10gpm. Most dosers that are more expensive are for higher flow rates. I got a gator-xl for 165$. It is built like a tank and the ferts inject on the exit pipe AFTER the dosing motor so it never gets gummed up or needs to be cleaned.
Gator-xl, hydro systems, mix-rites, dosatron all kill it for 150-300 depending on what features you want unless you have an orchard that you need more then 20 gpm.

 

[f-e]

It's interesting (and very valuable) to hear about the point of mixing being different. I guess for detergent you might want it inside to lube the seals, but for us it's just asking for trouble.

I still can't get below $300 and that's on another continent. I did see yours for $200 but it needed a $100 kit to make it adjustable.

The chinese one is under $100 delivered. I need to check if they have also moved on with parts availability and such I guess. It sounds like a few years ago you tried them. I have a few more names now, which should aid in my search.

Nice